Cable receptacles intended to be guided by such a guide conduit can for example be energy chains for receiving cables, hoses or flexible tubes in which adjacent members are articulated to each other, band chains in which the members are interconnected by a flexible band, or other cable receiving devices which are bowable in at least one plane.
Such guide conduits are known in various designs. In the case of longer travel distances, they are used in the horizontal or vertical direction. In horizontal travelling, they support a smooth and low-friction travel of the cable receptacle. To this end, the lower strand that is connected to the stationary connecting point is supported on the floor or on carrying rails of the guide conduit. The lateral walls of the guide conduit are arranged with little play with respect to the side members of the cable receptacle so that the same can be moved along an accurately linear travel path. After a shorter or longer self-supporting travel immediately after the redirection bow, the upper strand is usually supported the lower strand to be guided thereon in a sliding manner.
If the upper strand shall not be supported on the lower strand, e.g. if accumulating dirt or chips cause wear and tear during the sliding movement, the upper strand must be supported and also laterally guided by a guide conduit, especially at longer travel distances. A guide conduit which is suitable for this purpose is the subject of the present invention.
The term guide conduit is understood to be not only a continuous conduit which is closed laterally or at the bottom. The device is assumed to be one which supports or holds up the cable receptacle in at least two mutually vertically running directions transversely to the longitudinal direction of the cable guiding device. Accordingly, supporting or holding can also be provided in spaced-apart regions in the longitudinal direction of the cable receptacle so that the guide conduit can be open or discontinuous between these regions.
Known guide conduits for supporting an upper strand which is guided with a vertical distance from the lower strand involve much time and effort, since the upper strand has to be supported not only laterally but also on its lower side, and the support of the lower side must be carried out in such a manner that the passage of the redirection bow is not affected during the reciprocating movement of the cable receptacle. In addition, the support leads to an undesired high sliding friction.
A guide conduit of the above-described kind is known from DE 20 2007 005 478 U1. In this conduit, the support device and the switching device are designed as protrusions on the opposite legs of a rocker, said protrusions of the rocker alternately protruding over the inner lateral surface of the respective lateral wall into the interior of the guide conduit. The protrusions are formed as hemispheres pointing in the direction toward the interior of the guide conduit so that by the contact of the guide conduit in its longitudinal direction with the cable receptacle, said protrusions can be moved from their inwardly protruding first position to their second position in which they do not protrude inwards if the respective other protrusion is not contacted by the cable receptacle.
With the support device which is known from the above-mentioned document, the upper strand of the cable receptacle is supported and guided punctually at two respective opposite positions. Such a support device is particularly suitable for vertically movable cable receptacles in which vibrations of the strand which is connected to the movable connecting point and clashing of the strands shall be avoided. In horizontally movable and/or heavier cable receptacles, a more stable and safer support and guidance of the upper strand are desired.
A support device for the upper strand of a cable receptacle is also known for instance from DE 23 620 463 A1. The mechanism proposed in this document and which is effective between the gripper arms, which can pivot in the transverse direction and which grip under the upper strand, and the switching rockers, is relatively complicated and expensive. For guiding the upper strand and the lower strand laterally, separate tub portions are respectively provided on a supporting structure.
A further support device for the upper strand of a cable receptacle is disclosed in U.S. Pat. No. 4,129,277 A1. This device includes L-shaped supports having a long leg and a short leg arranged for pivoting about an axis in the region of the transition between the two legs transversely to the longitudinal direction of the cable receptacle. On the free ends of the long legs at the side facing the respective shorter leg, rollers are supported which include a bearing surface for supporting the upper strand of the cable receptacle, and a flange part for laterally guiding the upper strand on the side pointing to the long leg. From an outwardly tilted position of the L-shaped supports, in which they do not impede the movement of the cable receptacle through and between them, as a result of the lower strand being supported on the short legs which point to each other, said supports are erected into a position in which the rollers are effective for supporting and guiding the upper strand. If during the returning movement of the lower strand the short legs are no longer loaded by the weight of the lower strand, the L-shaped supports are moved back to the outwardly inclined position with the aid of spring forces. To make sure that the supports are pivoted apart and outwards, shackles are provided about the rollers in the longitudinal direction of the cable receptacle, and the redirection bow of the cable receptacle can strike against these shackles and thus cause the supports to be pivoted apart.
However, in this known device the support of the lower strand of the cable receptacle only takes place by the approximately linear contact area with the rollers. A lateral guidance of the upper strand is also limited to the contact areas on the flange parts of the rollers. The support and guidance are dependent on whether the supports are maintained in the vertically erected position due to the weight of the lower strand of the cable receptacle resting on the short leg. In relatively fast moving cable receptacles, vertically upwardly directed forces can be exerted on the lower strand as a result of vibrations so that a safe support and lateral guidance of the upper strand cannot always be guaranteed.
The present invention is based on the object of improving a guide conduit of the kind described at the beginning in such a manner that the upper strand of a low-wearing cable receptacle can be safely and stably guided in a sliding fashion using simple means.